Motion-transmitting drive chains are well known. Such chains are alternately known as or referred to as push chains, drive chains, and thrust chains. Regardless of what they are called, motion-transmitting drive chains are able to transmit an axial compressive load as well as exert a tensile force. Common chain on the other hand is incapable of transmitting a compressive load and is only able to exert a tensile force.
Motion-transmitting drive chains and common chains are both made up of successive, flexibly-connected links which are joined to each other by pins. In a common chain, the links are freely able to rotate around the pins in both directions. Unlike the links of a common chain, the links of a motion-transmitting drive chain are able rotate in only one direction. When the links of a drive chain are urged to rotate in the opposite direction, the chain becomes rigid and thereafter able to transmit a compressive axial load.
A problem with prior art drive chains is their susceptibility to buckling, if the line of action of a compressive force tends to rotate the links in the wrong direction or if the links are not sufficiently loaded to keep them locked. A drive chain that pre-loads the links of a drive chain such that they are less susceptible to buckling would be an improvement over the prior art.